Explore how America's electricity grid works — from historic generation mix trends (2019–2025) to hour-by-hour grid operations across 13 regions
Click a region to explore its energy data. Then choose between historic trends or hourly grid analysis.
Explore how the generation mix has changed across 7 years of EIA data.
Right now — this very second — grid operators are orchestrating a symphony of thousands of generators to deliver electricity to millions of homes, hospitals, data centers, and factories.
Every hour, they must perfectly balance supply with demand. The margin for error is razor-thin: even a small imbalance can cascade into blackouts.
What you see is every single hour of electricity generation in 2024 — 8,760 dots arranged in a grid. Each dot represents the grid's total output during one hour, sized by generation and colored by emission intensity.
Blue and green dots are the cleanest hours — nuclear, hydro, wind, and solar carried the load. Orange and red dots are the dirtiest: fossil generators were ramped to maximum.
Scroll to discover why annual accounting is misleading.
Nuclear and hydroelectric power form the grid's clean, firm foundation. They run 24/7/365 regardless of weather.
The chart shows all 8,760 hours of demand (gray area) with the clean baseload (blue area) overlaid. Look at the blue band — it barely moves. That's the steady, unwavering stream of carbon-free power.
This stacked area chart shows a typical summer day: 24 hours of generation broken out by fuel source. As demand climbs each morning, fossil generators ramp up. First efficient gas, then dirtier units.
The emission rate of every MWh changes dramatically by hour.
Wind and solar have transformed the grid. But they generate when nature allows, not when needed.
The heatmap grid shows 12 months of average 24-hour generation profiles — wind on top, solar on the bottom. Summer midday: solar floods the grid. Winter evenings: almost nothing. The pattern is dramatic and seasonal.
Annual Scope 2 gives one number — the single colored tile on the left showing the annual average emission rate in kg CO₂/MWh. It looks clean. Reassuring.
But the dot grid on the right reveals the reality: every single hour has a different emission rate. Some hours are nearly zero-carbon. Others are heavily fossil-fueled. The average hides the chaos.
Same grid. Two hours. Radically different resource mixes. The stacked bars show the fuel breakdown for this region's single cleanest and dirtiest hours of 2024.
The clean hour is dominated by nuclear and renewables. The dirty hour has fossil fuels stacked high. Look at how the total height and color composition change.
Hourly accounting reveals what annual numbers hide.
The transition: from reliable + affordable to reliable + affordable + clean.
Hourly matching tells markets: “We need clean power at 6 PM in January, not just sunny April afternoons.”
This drives investment in firm clean power, storage, and demand flexibility.
Data from EIA Form 930 Hourly Electric Grid Monitor, covering 2019–2025 annual trends and 2024 hourly generation across 13 grid regions.